Furthermore, to complement the assessment of biological parameters highly relevant to replication stress and oxidative DNA damage, we also examined the proliferation index (as a percentage of tumour cells positive for the Ki67 proliferation marker) and the presence and subcellular localization of the major oxidative DNA lesions, detected by an antibody to 8‐oxoguanine (8‐oxoG), both well‐established biomarkers used also in our previous studies (Bartkova et al., 2010; Kurfurstova et al., 2016). This evidence concerns the gene MKI67 and neoplasm.